The present disclosure relates to data storage systems, and more specifically, to migrating data within data storage systems.
A data storage system can have one or more storage tiers in one or more storage devices. Tiered storage is a data storage environment consisting of two or more kinds of storage devices delineated by differences in at least one of these four attributes: price, performance, capacity and function. Any significant difference in one or more of the four defining attributes can be sufficient to justify a separate storage tier.
Extents can be managed on tiered storage. An extent is a contiguous area of storage in a storage system. A tiered storage system may move extents between tiers to optimize its performance and capacity needs.